Multi Tone Generator

Here one another sound generator project is added is section of alarm and sound generator projects. We have tested and posted dozens of sound or tone generator projects. Now, here is multi-tone generator circuit which produces eight different types of tones. The tones produced by the circuit multi tone generator are of Bell, Ambulance Siren, Whistle, Machine gun Sound, Jingle, Police siren, Birds and Dual sound.

Circuit Description of Multi Tone Generator

The heart of the circuit multi tone generator is UM5561 IC (IC1) and the entire circuit is built around it. UM series IC is designed for tone generation. The eight tones produce by the circuit is divided by two channels and each channel contains four tones.

circuit diagram of multi tone generator

The output is taken from pin 3 of IC1 and is connected to base of transistor T1 through resistor R3 and VR1 for amplification. The third terminal of VR1 is connected to base of transistor T1 and is used as volume controller. The amplified signal from collector of IC1 is connected to base of transistor T2. Transistor T2 is driver transistor and used to drive loud speaker. A loud speaker is directly connected to output as shown in circuit diagram.

The circuit utilizes 3V power supply. Switch SW1 and SW2 is used for selection of beats. The cost of entire circuit is less then 1$.


Resistor (all ¼-watt, ± 5% Carbon)

R1 = 1.5KΩ

R2 = 120 KΩ

R3 = 1.2 KΩ

R4 = 1.8 KΩ

R5 = 5.6 KΩ

R6 = 220 KΩ

VR1 = 10 KΩ LIN.


C1 = 22 µF


IC1 = UM3561

T1, T2 = BC547


SW1 = ON/OFF Switch

SW2 = 4 Pole 4 Through Switch